The LM2576 series of regulators are monolithic integrated
circuits ideally suited for easy and convenient design of a
step-down switching regualtor(buck converter).
All circuits of this series are capable of driving a 3.0A load
with excellent line and load regulation. These devices are
available in fixed output voltages of 3.3V, 5.0V,12V, 15V,
and an adjustable output version.
These regulatiors were designed to minimize the number of externalcomponents to simplify the
power supply design. Standard series of inductors optimized for use with the LM2576 are offered
by several different inductor manufacturers.
Since the LM2576 converter is a switch-mode power supply, its efficiency is significantly higher in
comparison with popular three-terminal limear reguators, especially with higher input voltages.
In many cases, the power dissipated is so low that no heatsink is required or its size could
be reduced dramatically. A standard series of inductors optimized for use with the LM2576 are available from several different manufacturers. This feature greatly simplifies the design of
switch-mode power supplies. The LM2576 features include a guaranteed ±4% tolerance
on output voltage within specified input voltages and output load conditions, and ±10% on the
oscillator frequency (±2% over 0°C to 125°C).
External shutdown is included, featuring 80 (typical) standby current. The output switch includes
cycle-bycycle current limiting, as well as thermal shutdown for full protection under fault conditions.